1. Technical Field
The present disclosure generally relates to illuminating apparatuses, and particularly to an illuminating apparatus with a light emitting diode and phosphor films for emitting different colors of light.
2. Discussion of Related Art
Light emitting diodes (LEDs) are one kind of semiconductor element. Nowadays, LEDs are extensively used as light sources for illuminating apparatuses, due to their high luminous efficiency, low power consumption and long work life.
In some LED devices, to satisfy certain illuminating requirements, light mixing is employed. That is, light with different colors or wavelengths is emitted from different light emitting diodes, and such light is mixed to form light of a desired color or wavelength. For example, white light is obtained by mixing light emitted by red, green, and blue LED dies. However, because these three LED dies cannot occupy the same position in the LED device and must be arranged adjacent to each other, the light mixing is not necessarily thorough, and the light output from the LED device may be non-uniform. Alternatively, a light source module may use a blue LED as a primary light source to produce a final emission of white light. The blue light emitted from the blue LED strikes phosphor material of the light source module to generate secondary yellow color light. The combination of the yellow light and residual (unconverted) blue light produces white light. However, the phosphor is usually packaged within the blue LED itself. It is difficult to ensure that the phosphor is evenly distributed in the LED. If the phosphor is unevenly distributed, the light output from the light source module may be non-uniform.
Therefore, what is needed is an illuminating apparatus to overcome the above described shortcomings.